AKA: The Ghost Of Plots Past
So as you may be aware, this season ends on a cliffhanger that needed to be resolved in a big expensive movie (we'll get to it, don't worry). What that means, unfortunately, is that throughout the season there were episodes where either Gillian Anderson or David Duchovny wouldn't be available, because they'd be off shooting their movie scenes (and at least one episode where neither of them could be available). The affects the way they write the episodes, since there are multiple episodes this season which have to be centered around either Mulder or Scully, to give them time to be off set, and writing an episode to suit an actor's availability first and to tell a good story second is always a backward way to write it.